Electric light



(No Model.)

. C. I'. BECK.

ELECTRIC LIGHT.

Patented Jul v 14 No. 322,033. W

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UNITED STATES PATENT CHARLES F. BECK, OF PARIS, FRANCE, ASSIGNOR TO ATHOMAS S.v HARRISON, OF PHILADELPHIA, PENNSYLVANIA.

ELECTRIC LIGHT.

SPECIFICATION formingpart of Letters Patent No. 322,033, dated only-14, 1885.

Application tiled September l0, 1884. (No modell.) I

To' aZZ whom it may concern:

Beit known that I, CHARLES FREDERICK BECK, of Paris, in the Republic of France, have invented certain new and useful Improvements in vElectric Lamps.

The following is a specification of my im.

provements, reference being had to lthe accompanying drawings, wherein- Figure 1 represents a side View of the lamp proper and a vertical section through the in closing-globe of the same. Fig. 2 isa view at' right angles to the position shown in Fig.V 1. Figs. 3 and/1 are sectional views showing the position merely of theseveral parts at the lines a: a: andy y, respectively. Fig. 5 is a plan view of the-under side of the cap or cover -of the lamp, showing certain of the parts in horifrontal section, and Fig. 6' is a' .detail view of spring M.4 v

. In the drawings, A is a glass globe inclosing the apparatus, and attached by means of hooks i z' to the cap or cover'B, from which the va-4 rious parts of the lamp proper are suspended, and which in turn is provided withfan attachment, C, for securing the whole in position, said attachment C being preferably tubular in form toconceal the conducting-wires -An inclined strip, L, preferably. of vulcanite, is attached at the upper end of the cap C, said strip having a groove, t, upon one-oftits sides, being provided upon the other.- with a band of copper, E, extending along its entire length. Said band of copper is connected with the binding-post R, which forms an at-l strip L from the bottom, and," when inserted,

tachment for the connecting-Wire a.

At the bottom of thestrip E is a metallic spring, M, of sufficient size to afford a good conductor for the current, and at the bottom of said spring is a iin-ger, H, preferably of copper tipped with platinum, e, said copper finger H being rendered easily adjustable ver# tlcally inaslot, m, in the spring M by means' ofthe setserew m. Pulleys n n. are arranged on each side of the vulcanite strip. L, at or .near its upper end, and similar pulleys, d d,

on each side near its ,lowerl end. l p A pencil of carbon, F, lies in the' grooves of the strip L, and is provided at its upper 5' end with a cap, s, to which cords p p are attached, the said cordspassing down under the pulleys d, then upand over 'the pulley.f n', and being both fastened to a weight, b. A

bridle, o, having a friction-roller, c, is arranged at the bottom of the strip L, so as to -prevent -the displacement of the carbon pencil F from the groove t, but to permit its free descent under the influence of the .weight b. The spring M presses the finger H against the carbon pencil F, so as to a'ord a good electric contact between them.' The tip of the pencil F rests upon the end of a thin curved arm, N, preferably 'of copper tipped with platinum j, said arm beingattached b means of va hinge o r pivot, k, to the base u o the bindingscrew P,aftixed to the under side of the cap cr cover B, opposite to the point of attachment of the -vulc'anite strip. L. .v To Vthis binding-screw P the other wire, a, of the electrical circuit is aty tached.

side of the pointofcontact of the carbonA :pencil F therewith. 4

To place the parts in position (the glass globe -A being'detache'd,) the arm N is swung outward upon-its pivot 7c. Thel carbonpencil- F is thenvrun into the groove t of t-hevulcanlte the cap s (which is arranged to spring over the end of the carbon) isattached thereto. The

cordsp are then connected with the eye of the cap s, and passed over the respective pulleys d d and wn on each side of the strip L, and made fast to the weight b. The arm N isthen swung into position so that the tip of the carbon pencil F shall rest thereon, as shown in-Fig. 1. The plate, G, of porcelain, is inserted in the `jaw of the holder D,and secured by the screw g in such position that the end shall touch the tip of the carbon pencil F and shall rest upon the platinum end j of the arm N. Connection being properly made by means of the bindingposts Rand P with thewires a and a', respectively, the current from a dynamo or other source of electricity is turned onto said wires,

` (of which a' should be connected with the positive and a with the negative pole,) and the circuit is established through the copper strip.

l arm N. By reference to Fig. 1, it will be seen that the small portion 'of thegcarbon pencil F through which the current passes is in contact laterally with thplate G of porcelain; but'said plate forms at thistime no part of the circuit,

' the material being, when cold, a non-conductor. The passage of the current,howcver, heats the carbon tip, and by contact therewith the porcelain plate G, which, at a? high temperature, becomes measurably a conductor, and as soon as the tip `of the pencil F is dissipat'ed or wastes away by the action of the current, so that it nolonger touches the platinum j, the circuit establishes itself through a porp f' 'tion ofthe now heated porcelain plate G, which,

bythe resistance that it aii'ords tothe passage of the current, becomes highly incandescent. A The pressure of the spring M against the car,

bon pencil F holds it in contact with the side of the plate Grv withsuicient force to prevent its slipping entirely down so as to again rest upon the platinum i;,but at the same time the weight b tends to, press the carbon pencil downward, and hence to prevent it from etjtingout of contact with the porcelain byiea-V sonof the continued wasting away of thecarbon, should :such action take place. therefore necessary that there. should be a certain balance between the pressure of the spring M andthe-weight b, since itis desirable to maintainithe contact between the carbon pencil andthe porcelain plate at a prac- The ldistance of this point from the platinum tpj of the arm N is determined by the actual size of the respective parts and the strength of the current; lbut I 'have obtained good results by the separation y of a millimeter, thus, causing the current to pass 'through the porcelain to that extent. The adj ustability of the finger H in the spring M facilitates the arrangement of the contact and determines the extent of carbon 'through which it is expedient to maintain the current.

I prefer to use porcelain as the interposed material-to be rendered incandescent, since I have found that it becomes very slightly pasty under the temperature attained, and hence affords a good contact for the end of the carbon pencil, and prevents the latter from slipping down; b'ut magnesia and various other refrac- It -is tory oxides and earths compressed into a hard plate may be substituted therefor. The qualities which I consider most important for the 'classification of such substitutes are as follows:

-ductor of such resistance as to become incandescent under the passage of the current.

The mechanical devices above described may be varied without substantial departurelfrom theprinciple of my invention. Thus, instead of depressing the carbon by means of a weight and maintaining it against the porcelain surface by means of a spring, other equivalent devices may be employed for the purpose, and hence, while I deem the apparatus above described a convenient embodiment'of my invention, I do not desire to limit my claim to that exact method of construction.

Having thus described my invention, what I claim 'as new, and desire to secure by Letters Patent, is-

1. In an incandescent electric lamp,thecom` bination of a permanent electrode, a carbon electrode arranged to rest thereon, a plate of porcelain or other equivalent material i arl ranged in contact with said electrodes, and means whereby, after the establishment of a current vsufficient to develop the conductingpoWer of said plate by heat, the said carbon electrode is maintained in contact with said plate ata substantially constant distance from said permanent electrode, the whole operating in the manner set forth.

2. In an electric lamp operating by the incandescence of a piece of porcelain or equivalent material, tlte combination lof a holder for said piece, a permanent electrode, a carbonholder, and a' pressure device for said holder against said piece at a substantially constant distance from said permanent electrode, the whole operating substantially as set forth.

3. The combinationof the swinging arm N,

-the holder D, having a clamping device at its lower end, the inclined strip L, having a way or groove on its edge for retaining the carbon, the adjustable finger H, and suitable devices for pressing said finger laterally against the carbon and depressing the carbon longitudinally, substantially as and for the purposes setforth.

v CH. F. BECK.

Witnesses: v A

WM. H. MYERS. J. W. DoUGLAss.

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